Chrysler Voyager. Manual — part 29

Symptom:

P0420-1/1 CATALYTIC CONVERTER EFFICIENCY

When Monitored and Set Condition:

P0420-1/1 CATALYTIC CONVERTER EFFICIENCY

When Monitored:

After engine warm up to 70°C (158°F), 180 seconds of open throttle

operation, at a speed greater than 18 mph and less than 55 mph, with the engine at
1200-1700 rpm and MAP vacuum between 15.0 and 21.0 inches of mercury (Hg).

Set Condition:

As catalyst efficiency deteriorates, the switch rate of the downstream O2

sensor approaches that of the upstream O2 sensor. If at any point during the test the
switch ratio reaches a predetermined value a counter is incremented by one.

POSSIBLE CAUSES

GOOD TRIP EQUAL TO ZERO

VISUALLY INSPECT CATALYTIC CONVERTER

EXHAUST LEAK

ENGINE MECHANICAL CONDITION

AGING O2 SENSOR

CATALYTIC CONVERTER

TEST

ACTION

APPLICABILITY

1

NOTE: If a O2 Sensor DTC(s) set along with the Catalytic Converter
Efficiency DTC diagnose the O2 Sensor DTC(s) before continuing.
NOTE: Check for contaminates that may have damaged the O2 Sensor and
Catalytic Converter: contaminated fuel, unapproved silicone, oil and cool-
ant, repair necessary.
Turn the ignition on.
With the DRBIII

t, read DTC’s.

Is the Good Trip displayed and equal to zero?

All

Yes

→ Go To 2

No

→ Refer to the INTERMITTENT CONDITION symptom in the

Driveability category.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

2

Inspect the Catalytic Converter for the following damage.
Damage Catalytic Converter, dent and holes.
Severe discoloration caused by overheating the Catalytic Converter.
Catalytic Converter broke internally.
Leaking Catalytic Converter.
Were any problems found?

All

Yes

→ Replace the Catalytic Converter. Repair the condition that may

have caused the failure.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 3

115

DRIVEABILITY - SBEC

TEST

ACTION

APPLICABILITY

3

Start the engine.
Inspect the exhaust for leak between the engine and the O2 sensor.
Inspect the exhaust for leaks between the engine and the appropriate rear O2 Sensor.
Are there any exhaust leaks?

All

Yes

→ Repair or replace the leaking exhaust parts as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 4

4

Check the exhaust for excessive smoke caused by an internal problem in the engine.
Is a engine mechanical condition present?

All

Yes

→ Repair the engine mechanical condition as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 5

5

A new rear O2 Sensor along with an aging front O2 Sensor may cause the DTC to set.
Review the vehicles repair history.
Has the rear O2 Sensor been replace without replacing the front O2 Sensor?

All

Yes

→ Replace the Front O2 Sensor as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 6

6

If there are no possible cause remaining, view repair.

All

Repair

Replace the Catalytic Converter.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

116

DRIVEABILITY - SBEC

P0420-1/1 CATALYTIC CONVERTER EFFICIENCY —

Continued

Symptom:

P0441-EVAP PURGE FLOW MONITOR

When Monitored and Set Condition:

P0441-EVAP PURGE FLOW MONITOR

When Monitored:

With engine temperature greater than 71°C (160°F), fuel control in

closed loop, engine idling for 200 seconds, no low fuel, MAP less than 23.6 inches mercury
and barometric altitude less than 8,000 feet.

Set Condition:

After having passed the Leak Detection Pump (LDP) test, no air flow

through the evaporative system is detected by the evap monitor.

POSSIBLE CAUSES

GOOD TRIP EQUAL TO ZERO

EVAP PURGE SOLENOID LEAKS/STUCK OPEN

EVAP PURGE SOLENOID STUCK CLOSED

EVAP PURGE SOLENOID VACUUM SUPPLY

EVAP PURGE HOSE SOLENOID TO CANISTER

EVAP PURGE HOSE CANISTER TO FUEL TANK

EVAP CANISTER

TEST

ACTION

APPLICABILITY

1

Turn the ignition on.
With the DRBIII

t, read DTC’s.

Is the Good Trip Counter displayed and equal to zero?

All

Yes

→ Go To 2

No

→ Refer to the INTERMITTENT CONDITION symptom in the

Driveability category.
Perform POWERTRAIN VERIFICATION TEST VER - 5.

2

NOTE: After disconnecting the Evap Purge Solenoid vacuum connections,
inspect the lines and solenoid for any signs of contamination from the EVAP
Canister. This may indicate a faulty rollover valve. Replace/repair as
necessary.
Turn the ignition off.
Disconnect the vacuum hoses at the Evap Purge Solenoid.
Using a hand vacuum pump, apply 10 inches of vacuum to the Evap Purge Solenoid
vacuum source port on the component side.
Does the Evap Purge Solenoid hold vacuum?

All

Yes

→ Go To 3

No

→ Replace the Evap Purge Solenoid.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

117

DRIVEABILITY - SBEC

TEST

ACTION

APPLICABILITY

3

Using a hand vacuum pump, apply 10 inches of vacuum to the Evap Purge Solenoid
vacuum source port on the component side.
Turn the ignition on.
Observe the vacuum gauge.
With the DRBIII

t, actuate the EVAP Purge Solenoid .

Does the vacuum drop when the solenoid is actuated?

All

Yes

→ Go To 4

No

→ Replace the Evap Purge Solenoid.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

4

Turn the ignition off.
Carefully inspect the Evap Purge Solenoid vacuum supply hose for proper routing.
Check for a pinched or plugged hose from the throttle body to the Purge Solenoid.
Inspect the vacuum port at the throttle body for any damage or plugging.
Were any problems found?

All

Yes

→ Repair the vacuum supply hose/tube as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 5

5

Visually inspect the Evap Purge hose from the Evap Purge Solenoid to the Evap
Canister.
Look for any physical damage such as a pinched, plugged, ripped or dry rotted hose.
Were any problems found?

All

Yes

→ Repair or replace hose as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 6

6

Visually inspect the Evap Purge hose from between the Evap Canister and the Fuel
Tank.
Check for any physical damage such as a pinched, plugged, ripped or dry rotted hose.
Were any problems found?

All

Yes

→ Repair or replace hose as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Go To 7

7

Visually inspect the Evap Canister for the following.
Check for physical damage or signs of fuel that has entered the canister.
Check for signs of fuel, this may indicate a bad rollover valve.
Were any problems found?

All

Yes

→ Repair or Replace as necessary.

Perform POWERTRAIN VERIFICATION TEST VER - 5.

No

→ Test Complete.

118

DRIVEABILITY - SBEC

P0441-EVAP PURGE FLOW MONITOR —

Continued